Graphene Oxide Cement Research Articles

Experimental study and analysis of the static and dynamic mechanical properties of graphene oxide cement soil under composite salinity erosion

In coastal and saline-alkali regions, cement soil materials face significant challenges from salt erosion and both dynamic and static loads, threatening their structural stability. To enhance the mechanical properties of cement soil, this study explores the incorporation of graphene oxide (GO). We subjected GO cement soil specimens to various concentrations of a composite salt solution (with a NaCl to Na2SO4 mass ratio of 1:1) in erosion experiments lasting 7 and 30 days. The specimens were analyzed through unconfined compressive strength tests, split Hopkinson pressure bar (SHPB) tests, and scanning electron microscopy (SEM) to examine changes in stress-strain curves, peak stress, and energy dissipation. The results indicate that the dynamic and static peak stresses, energy absorption, and energy absorption efficiency of the GO cement soil specimens are inversely related to the concentration of the mixed salt solution. Notably, in a 4.5 g/L erosion environment after 7 days, an increasing trend was observed in static peak stress, energy absorption, and energy absorption efficiency. Additionally, when the salt concentration was fixed, these properties showed a positive correlation with impact gas pressure. SEM analysis revealed that the nucleation effect of GO and its strong bonding with the cement matrix significantly improved the microstructure of the specimens by reducing pores and defects, thus enhancing density and overall performance. Furthermore, in an 18 g/L erosion environment, a notable presence of ettringite (AFt) was identified in the GO cement soil specimens.

Deep mining the mechanical behavior of graphene oxide–cement composites using data-driven artificial intelligence techniques

This study presents a data-mining workflow for mining potential information in graphene oxide-cement composite (GOCC) mechanics datasets using data-driven artificial intelligence techniques for enhancing data integrity and for data augmentation using semi-supervised learning. The obtained prediction models for the compressive, flexural, and tensile strengths of the GOCC had high R2 (0.98, 0.94, and 0.95) and low root mean square error (2.84, 0.80, and 0.34) in the real test set. The interpretability analysis of the black-box model showed that an appropriate GO admixture is critical; the GO thickness and linear size mainly affected its compressive strength and flexural strength, respectively. The 50 elites resulting from the search for the optimal mechanical properties of the GOCC in the developed model constituted the Pareto front, providing a suitable parameter design range for the GOCC. This study is essential for understanding the mechanical laws of GOCC and developing efficient design strategies.

Influence of Laboratory Synthesized Graphene Oxide on the Morphology and Properties of Cement Mortar.

The introduction of Graphene Oxide (GO), a nanomaterial, has shown considerable promise in improving the mechanical properties of cement composites. However, the reasons for this improvement are not yet fully understood and demand further research. This study aims to understand the effect of laboratory-produced GO, using Tour's method, on the mechanical properties and morphology of cement mortar containing GO. The GO was characterized using Fourier-transform infrared spectroscopy, X-ray Photoelectron Spectroscopy (XRD), X-ray powder diffraction, and Raman spectroscopy alongside Scanning electron microscopy (SEM). This study adopted a cement mortar with GO percentages of 0.02, 0.025, 0.03, 0.035, and 0.04 with respect to the weight of the cement. The presence of GO in cement mortar increased the density and decreased the consistency and setting times. At the optimum of 0.03% GO viscous suspension, the mechanical properties such as the 28-day compressive strength, splitting tensile strength, and flexural strength were enhanced by 41%, 83%, and 43%, respectively. In addition, Brunauer-Emmett-Teller analysis indicates an increase in surface area and volume of micropores of GO cement mortar, resulting in a decreased volume of mesopores. The improvement in properties was due to increased nucleation sites, calcium silicate hydrate (CSH) density, and a decreased volume of mesopores.

RETRACTED: Investigation on fluidity, microstructure, mechanical and durability properties of snail shell based graphene oxide cement composite material

• Inclusion of Snail Shell Powder with Graphene Oxide Cement Composite offers Improved Dispersion. • Replacement of Cement with Snail shell powder in Graphene oxide Cement composite helps to enhances the fluidity of composite. • Snail shell-based Graphene Oxide Cement Composite Helps to the formation of Ettringite. In recent years, there has been a more usage of Graphene Oxide nanomaterial to enhance the desirable qualities of cement-based composites. The fluidity of cement composites and the workability of concrete, on the other hand, may be lowered as a result of the introduction of graphene oxide (GO). In this research, a simple and inexpensive additive snail shell powder was employed to increase the fluidity of graphene oxide cement composites. Additionally, the microstructure, mechanized, and durableness performance of snail shell (SS) based graphene oxide (GO) cement composites was studied. Snail-Shells are examples of bio-shell debris that is wasted from restaurants and the seas every day. Because of poor maintenance of waste, SS are deposited as rubbish on vacant areas and in landfills. The snail shell powder has a spherical shape and has a pozzolanic character, similar to that found in cement. In the current study, snail shell powder was employed in GO-cement composites to substitute a portion of the cement, and the performance of the composite material's fluidity, microstructure, mechanical, and durability characteristics were investigated. The impact of snail shell powder was investigated at 10 wt%, 15 wt%, and 20 wt%, replacement of cement, with graphene oxide (GO) addition ranging from “0.01 wt%, 0.02 wt%, 0.03 wt%, and 0.04 wt%”. The amount of snail shell powder added to the GO composite enhanced the fluidity. A result of the reduced water requirement, the spherical form of the snail shell powder (SSP) and the pozzolanic nature of the SSP, the improved fluidity of the GO-cement composite was obtained. The SEM examination were used to establish the micro structural study of the cement composite. In the SEM pictures, it could be shown that the combination of SS and GO changed the nature of structure of the composite from one that was porous to one that was significantly pore filled, resulting in better mechanical and durability characteristics. At 3, 7, and 28 days of curing, snail shell based GO-cement composites demonstrated stronger compressive and flexural strengths than the control sample, despite the fact that the snail shell powder dose was less than 20 % of the total weight of the cement. Finally, the inclusion of snail shell powder material to the GO-cement composite resulted in an excellent solution to the fluidity issue that had been encountered.

Investigation on fluidity, microstructure, mechanical and durability properties of snail shell-based graphene oxide cement composite material

Investigation on fluidity, microstructure, mechanical and durability properties of snail shell-based graphene oxide cement composite material

Efficient Use of Graphene Oxide and Silica Fume in Cement-Based Composites.

Incorporation of graphene oxide (GO) and silica fume (SF) to cement composites enhances their mechanical properties if suitable proportional amounts of GO and SF are used. This study presents a simplified approach to determine experimentally the optimum GO and SF contents that should be added to the cementitious mixture to obtain a proper and stable dispersion of GO sheets within the cement matrix. Composite mortar specimens with different GO and SF contents were designed and tested under flexural and compression loading. The phase formation and the microstructure of selected samples were also investigated to give an in-depth interpretation of the test results. The main criterion to determine the GO and SF contents was the ultimate strength required of the GO–cement composite. It was found that there was a composite interaction between the SF and GO contents in the cementitious mixture, which an envelope surface could describe if all other mix design parameters are kept constant.

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

Effect of High-Dispersible Graphene on the Strength and Durability of Cement Mortars

Graphene’s outstanding properties make it a potential material for reinforced cementitious composites. However, its shortcomings, such as easy agglomeration and poor dispersion, severely restrict its application in cementitious materials. In this paper, a highly dispersible graphene (TiO2-RGO) with better dispersibility compared with graphene oxide (GO) is obtained through improvement of the graphene preparation method. In this study, both GO and TiO2-RGO can improve the pore size distribution of cement mortars. According to the results of the mercury intrusion porosity (MIP) test, the porosity of cement mortar mixed with GO and TiO2-RGO was reduced by 26% and 40%, respectively, relative to ordinary cement mortar specimens. However, the TiO2-RGO cement mortars showed better pore size distribution and porosity than GO cement mortars. Comparative tests on the strength and durability of ordinary cement mortars, GO cement mortars, and TiO2-RGO cement mortars were conducted, and it was found that with the same amount of TiO2-RGO and GO, the TiO2-RGO cement mortars have nearly twice the strength of GO cement mortars. In addition, it has far higher durability, such as impermeability and chloride ion penetration resistance, than GO cement mortars. These results indicate that TiO2-RGO prepared by titanium dioxide (TiO2) intercalation can better improve the strength and durability performance of cement mortars compared to GO.

Investigation on preparation and multifunctionality of reduced graphene oxide cement mortar

For modern concrete materials and structures, how to realize the multifunctional application is still a challenge. The introduction of functional components into concrete materials is the most effective method. The present study successfully develops a new avenue to prepare rGO suspension with excellent dispersibility and stability through the combination of dispersant and ultrasonic pre-dispersion. This rGO suspension is added to the cement-based material, resulting in the improvement of mechanical and functional properties. The compressive and flexural strength of mortar are increased by 45% and 50% at 3 days, respectively. Meanwhile the hydration heat and pore structure are improved up to doping 2.00 wt% rGO. Moreover, the resistivity and thermal conductivity of mortar are decreased by 45% and increased by 23%, while the electromagnetic shielding effectiveness of cement paste is increased by 45%. In addition, the pressure-sensitive property of mortar increases first and then decreases with the increases of rGO content, wherein the largest stress and strain sensitivity coefficient can reach up to 1.28%/MPa and 147.80 with 2.00 wt% rGO. These results demonstrate that doping rGO is a promising approach to the improvement of the functionality of cement-based materials resulting from the doping rGO is attributed to, the formation of a conductive network structure with the continuous phase in the cement matrix when rGO content reached percolation threshold.

Influence of the molecular structure of a polycarboxylate superplasticiser on the dispersion of graphene oxide in cement pore solutions and cement-based composites

For graphene oxide (GO) to fully exert its reinforcing and toughening functions in cement-based composites, it must be well-dispersed in the cement matrix. In this study, the dispersion behaviour of polycarboxylate superplasticisers (PCEs) with different charge densities and side-chain lengths in the treatment of GO in cement pore solution was studied using ultraviolet spectroscopy, visual sedimentation, and optical microscopy. The results show that all of the molecular structures of PCE can effectively remedy the agglomeration behaviour of GO in cement pore solution. However, for a fixed side-chain length, a higher charge-density PCE structure is better for GO dispersion, and for a fixed charge-density, a longer side-chain is better for GO dispersion. PCEs are adsorbed on the surface of GO through the bridging action of calcium ions (Ca2+) in a cement pore solution. First, the agglomeration of Ca2+ complexed by GO is effectively hindered by steric hindrance due to the side-chains. Second, the carboxyl groups of the PCE main chain complex with Ca2+ to reduce the free Ca2+ concentration near the GO sheets. For a fixed side-chain length, a higher charge density promotes GO dispersion by increasing electrostatic repulsion and decreasing the free Ca2+ concentration. For a fixed charge density, a longer side-chain substantially increases steric hindrance and promotes GO dispersion. In general, PCEs with higher charge density and longer side-chains are more suitable for manufacturing GO cement composites.

Strength properties of graphene oxide cement composites

Ordinary Portland Cement (OPC) is the key ingredient in concrete, and it is the primary choice in the construction and building environment. Emerging multi-functional materials have gained popularity by incorporating into OPC due to its excellent engineering properties. OPC resembles poor resistance to crack formation, low tensile strength, and strain capacity due to its brittle nature. Graphene and its derivatives like Graphene Oxide, Carbon Nano Fibres, Carbon Nano Tubes, and silica particles have shown a pathway in forming a super concrete by their extraordinary mechanical properties. Graphene oxide directly interacts with cement particles due to its excellent interfacial interaction properties. This paper represents the research on enhanced traditional concrete properties with Graphene Oxide. GO is added at several percentages like 0.01%, 0.02%, 0.03%, 0.04%, 0.05% by weight of cement to investigate the strength properties of cementitious composites. Nano structural properties and variations in hydration of cement are investigated by XRD, and AFM analysis. SEM, EDX tests determine the changes in mineral compounds when converted into hydrated crystals in the cement matrix. Addition of Graphene Oxide to cement provides a new aspect in understanding silicate hydrate phase changes. This will provide a potential for Nano Technology challenges in the construction industry and energy consumption reduction.

Physiochemical and mechanical properties of reduced graphene oxide–cement mortar composites: Effect of reduced graphene oxide particle size

The use of graphene derivatives to improve the performance of cement mortar composites has received significant attention in recent years. However, because of diversity of graphene derivatives and their properties, which depend on their preparation, it is critical to consider their size, surface chemistry, crystallinity, surface area, and impurity. In particular, there is still lack of understanding on the influence of the graphene particle size on the performance of cement mortar composite. This paper presents the study on the size effect of reduced graphene oxide (rGO) on physiochemical and mechanical properties of cement mortar composites. A series of rGOs with different particle sizes were prepared by different sonication times of 1, 2, 4, 6, and 8 h and then added with optimum dosage of 0.1% to the composites. The mechanical test results revealed that the composite containing rGO with 0.1% dosage and particle size of 169.8 ± 5.8 nm prepared with 4 h sonication time has 53% and 91% higher tensile and compressive strengths at 28 days than the plain cement mortar composite, respectively, which are higher than those obtained by the use of rGO with particle size of 245.0 ± 29.3 nm prepared with 1 h sonication time. This is explained by the higher molecular bonding, hydration degree, and crystallinity of the composite incorporating rGO with a smaller particle size. This study provides a valuable contribution toward better understanding of the influence of rGO particle size on the properties of cementitious composites to optimize their performance.

Rheological Behaviors of Edge-Oxidized Graphene Oxide Cement Composites

AbstractThis paper presents investigations on the effects of edge-oxidized graphene oxide (EOGO) on the rheological performance of cement composites. EOGO is produced by a mechanochemical process t...

Static and Cyclic Flexural Behaviors of Edge-Oxidized Graphene Oxide Cement Composites

AbstractThis paper investigates the flexural fatigue behavior of cement mortar mixed with edge-oxidized graphene oxide (EOGO), a carbon nanomaterial reinforcing cement hydration products. EOGO is p...

Modelling and Experimentation on Mechanical Properties of Graphene-Oxide Cement

Cementitious nano-composites have recently attracted considerable research interest in order to improve their properties such as strength and durability. Graphene oxide (GO) is being considered as an ideal candidate for enhancing the mechanical properties of the cement due to its good dispersion property and high surface area. Much of work has been done on experimentally investigating the mechanical properties of GO-cementitious composites; but there are currently no models for accurate estimation of their mechanical properties, making proper analysis and design of GO-cement based materials a major challenge. This paper attempts to develop a novel multi-scale analytical model for predicting the elastic modulus of GO-cement taking into account the GO/cement ratio, porosity and mechanical properties of different phases. This model employs Eshelby tensor and Mori-Tanaka solution in the process of upscaling the elastic properties of GO-cement through different length scales. In-situ micro bending tests were conducted to elucidate the behavior of the GO-cement composites and verify the proposed model. The obtained results showed that the addition of GO can change the morphology and enhance the mechanical properties of the cement. The developed model can be used as a tool to determine the elastic properties of GO-cement through different length scales.

Mechanical properties and microstructure of graphene oxide cement-based composites

Aiming to improve the flexural and compressive strength of cement, graphene oxide (GO) was incorporated into the production of cement-based composites in this study. The effects of the GO content and water/cement (w/c) ratio on the mechanical properties and microstructure of GO–cement composites were systematically investigated through experimental tests. Testing results show that with a constant w/c ratio, the flexural and compressive strengths of the developed GO–cement composites increased first and then declined with respect to the increase in GO content. Specifically, the increase in flexural strength was more significant than that in compressive strength, indicating that the addition of GO could help improve the toughness of cement composites. Additionally, a combination of a w/c ratio of 0.35 and a GO content of 0.05 wt% led to both the highest flexural and compressive strengths. The investigation of the composition–microstructure–strength relationship shows that the introduction of GO could help improve the macroscopic properties for the cement-based composites via improving the microstructure of cement hydration products, refining the crystal size, and forming a denser and more uniform network structure. The filling effect, hydration effect and nucleation effect of GO could be optimized with an appropriate combination of w/c ratio and GO content.

Nano-cement composite with graphene oxide produced from epigenetic graphite deposit

This study presents the development of a nano-cement composite with graphene oxide (GO) carbon-based nanomaterials synthesized from a high-purity epigenetic graphite deposit. Diamond drill sampled graphite mineralization was upgraded through beneficiation and purification to recover a high-purity graphite product (99.9% graphitic carbon “Cg”). An alternate and improved chemical oxidation process based on the Modified Hummers method was adopted for the synthesis of GO from high-purity graphite. Microstructural analysis were performed to characterise GO. The GO consists of OH, C=O, COOH, and C-O-C functional groups with a layer thickness of 1.2 nm, 2 to 3 layers of graphene, an interlayer distance of 0.90 nm and a Raman (ID/IG) ratio of 0.79. The effect of 0.02, 0.04, and 0.06 wt% GO of cement on the composite workability, hydration, microstructure, mechanical and transport properties was determined. Increasing the concentration of GO in the composite decreased the workability due to the hydrophilic nature of the 2D planar surface. The rate of hydration accelerated and the cumulative hydration heat increased with the increasing proportions of GO in the composite. GO dosages about 0.02 and 0.04 wt% of cement in the composites resulted the maximum enhancement of compressive and flexural strength by 83 and 26%, respectively, compared to the control mix (0 wt% GO). The microstructural investigation shows that GO enhanced the hydration of calcium hydroxide (CH) and calcium silicate hydrate (C-S-H) during the nucleation and growth stages, filled pores, bridged micro-cracks and created interlocking between the cement hydration products. Collectively, these effects ultimately improved the mechanical properties of the composites. Also, in this process, the 0.02 and 0.04 wt% GO cement composite increased the electrical resistivity by 11.5%, and decreased the sorptivity by 29%, respectively, both of which improved the overall performance of the composite.

Micro-mechanical properties and multi-scaled pore structure of graphene oxide cement paste: Synergistic application of nanoindentation, X-ray computed tomography, and SEM-EDS analysis

In this study, the microstructure and micromechanical properties of graphene oxide (GO) cement-based materials are investigated. Nanoindentation with statistical deconvolution was used to determine the elastic properties of constituent phases. Besides, combined with scanning electron microscopy (SEM) equipped with energy-dispersive spectrometer (EDS) and backscattered electrons (BSE), each phase of hardened cement paste was identified and quantified as well. X-ray computed tomography (XCT) microscope was applied to determine the morphology of micrometer-size pores, while mercury intrusion porosimetry (MIP) was used to capture the volume fraction of smaller pores (nano-scale). The combined use of XCT and MIP offered an effective approach for further understanding the effect of GO on pore structure at multi-scale. The synergistic analysis of microstructure and micromechanical properties at multi-scale provides valuable information towards the material design of cement-based materials with nanomaterials.

Influence of Graphene Nanosheets on Rheology, Microstructure, Strength Development and Self-Sensing Properties of Cement Based Composites

In this research, Graphene oxide (GO), prepared by modified hammer method, is characterized using X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectrometry and Raman spectra. The dispersion efficiency of GO in aqueous solution is examined by Ultraviolet–visible spectroscopy and it is found that GO sheets are well dispersed. Thereafter, rheological properties, flow diameter, hardened density, compressive strength and electrical properties of GO based cement composite are investigated by incorporating 0.03% GO in cement matrix. The reasons for improvement in strength are also discussed. Rheological results confirm that GO influenced the flow behavior and enhanced the viscosity of the cement based system. From XRD and Thermogravimetric Analysis (TGA) results, it is found that more hydration occurred when GO was incorporated in cement based composite. The GO based cement composite improves the compressive strength and density of mortar by 27% and 1.43%, respectively. Electrical properties results showed that GO–cement based composite possesses self-sensing characteristics. Hence, GO is a potential nano-reinforcement candidate and can be used as self-sensing sustainable construction material.

The role of graphene oxide in limited long-term carbonation of cement-based matrix

Carbonation leads to a drop in the alkalinity of cementitious materials because carbon dioxide mainly attacks calcium phases and converts them into carbonated phases. The carbonation rate depends on the ease with which carbon dioxide can proceed from outer to internal surfaces. In this study, graphene oxide (GO) is used to enhance the resistance of cement matrix against carbon dioxide attack. Graphene oxide was added to cement mix sufficient amount of water to produce cementitious matrix. Visual colour change, porosity and compressive strength tests were performed to investigate effect of the carbonation on cementitious materials. The results show very low carbonation depth in the graphene oxide cement mix. After 18 months, the plain cement mixture was nearly fully carbonated compared to only about 4 mm for the GO mix. This significant result can be attributed to the influence of interlocking of GO to different anionic and cationic ions.